Abstract
A traumatic hemorrhage is fatal due to the great loss of blood in a short period of time; however, there are a few biomaterials that can stop the bleeding quickly due to the limited water absorption speed. Here, a highly absorbent polymer (HPA), polyacrylate, was prepared as it has the best structure-effectiveness relationship. Within a very short period of time (2 min), HPA continually absorbed water until it swelled up to its 600 times its weight; more importantly, the porous structure comprised the swollen dressing. This instantaneous swelling immediately led to rapid hemostasis in irregular wounds. We optimized the HPA preparation process to obtain a rapidly water-absorbent polymer (i.e., HPA-5). HPA-5 showed favorable adhesion and biocompatibility in vitro. A rat femoral arteriovenous complete shear model and a tail arteriovenous injury model were established. HPA exhibited excellent hemostatic capability with little blood loss and short hemostatic time compared with CeloxTM in both of the models. The hemostatic mechanisms of HPA consist of fast clotting by aggregating blood cells, activating platelets, and accelerating the coagulation pathway via water absorption and electrostatic interaction. HPA is a promising highly water-absorbent hemostatic dressing for rapid and extensive blood clotting after vessel injury.